In adopting a mean value from this summary it has been deemed best to reject the obser-
vations of October 12, 1903, as probably defective, owing to improper setting for the magnetic
meridian. From the remaining sixty sets of observations with two needles each the resulting
inclination at Teplitz Bay is
83 J2.'4 for epoch J904.J3.
3 I2
SCIENTIFIC RESULTS OF ZIEGLER POLAR EXPEDITION
SECULAR CHANGE IN MAGNETIC INCLINATION
Observations were made for inclination, as noted in the tabulation of dip results, at the
Italian magnetic station of 1899 and 1900. In order to have the resulting values apply to the
same mean time at both stations observations were first made at the Italian station with one
polarity of the marked end of each needle ; the instrument was then transferred to pier D in
the observing hut, where complete sets with each needle were made, and finally the comparison
was completed by observing with second polarity of the marked end of each needle at the Italian
station. Assuming a linear change in diurnal variation over the period of observation, the
mean results at the two stations are directly comparable. The mean resulting difference in
magnetic dip between the two locations is 7/3 as adopted from the following tabulation of the
comparisons :
Date
Local
mean
time
Mean dip
observed at
Italian
station
Local
mean
time
Mean dip
observed at
Ziegler
station
A I Zieg-
ler station
to Italian
station
Weight
1904
June 6
h m
15 24
/
83 02.4 N
h m
15 22
/
83 14.6 N
/
12.2
i
June 20
15 30
3-3
15 28
10.8
7-5
2
June 27 16 18 14.6
Whence weighted difference e
16 18
dooted
19-3
- 4-7
2
7-3
The comparison of June 6 is given weight of one against two for each of the other com-
parisons by reason of the observer's note regarding discovery of iron bolt at foot of pier on
June 20. There being no reason to assume any change in local magnetic conditions at so
isolated and unfrequented a locality, we may assume the same difference at the time of the
Italian Expedition.
Commander Cagni's observations resulted as follows :*
D a t e Number of de- Mean observed
terminations inclination
August 21, 22, 1899 4 83 25/0 N
July 10, 16, 17, 23, 1900 9 83 01.2
whence the mean value 83 13/1 N for the epoch 1900.09. Referred to the Ziegler Polar
Expedition station, this becomes 83 13/1 4- 7/3 = 83 20/4. The value for the epoch
1904.13, as above, is 83 12/4 N. Both of these series are uncorrected for diurnal variation.
Each, however, consists of observations made at various parts of the day, so that the means
may be assumed as applying practically to mean of day at their respective epochs. Thus in
four years the northerly magnetic inclination in the region of Teplitz Bay has decreased 8'.
Hence the rate of change in magnetic inclination due to secular variation, assuming this effect
to be a linear function during the elapsed interval, is
2' per year.
This value is, while of the same sign, considerably smaller than that taken by Professor
Palazzo as a result of his discussion of Commander Cagni's observations, viz. , 24'. He,
however, considers this determination as not very reliable, owing to the short period between
the inclination observations, and also the great variation between the individual values obtained.
* Osservazioni scientifiche esequite durante la spedizione Polare di S. A. R. Luigi Atnedeo di Savoia, Duca
degli Abruzzi, 1899-1900. Milan, 1903. Pp. 462-475. (Relazione sulle osservazioni magnetiche fatta dal Pro-
fessore Luigi Palazzo.)
MAGNETIC OBSERVATIONS 313
The annual rate above deduced is further confirmed by the fact that it is of practically the same
order as values obtained at other Arctic stations. Thus, for example, for Cape Thordsen and
Mossel Bay, Spitzbergen, Dr. Solander* has deduced the annual rates of increase in magnetic
inclination as 0/4 and o.'8 for the periods 1883.2 to 1899.7 and 1873.5 to 1899.7 respectively.
HORIZONTAL INTENSITY
INSTRUMENT, METHODS, AND RESULTS
Observations for horizontal intensity were made, as already stated, with magnetometer
No. IIII loaned by the United States Coast and Geodetic Survey. For the various standardi-
zation observations with this instrument before and after the work of the expedition, as also
for the constants and methods of reduction used, see pages 6 to n. Determinations were made
generally on Monday afternoons and Tuesday mornings, but it was not possible before the
advent of daylight to adhere strictly to this program. In these observations for intensity the
time of a set of fifty oscillations was observed in the usual manner before and after deflection
observations. Sometimes these were repeated ; at other times the final set of oscillations was
lost, owing to the failure to transit of the selected scale division.
The fortieth division, being near the middle of the scale, was the one whose transit was
chosen. The initial amplitude of the oscillation was usually made about one degree in order
to increase the probability of the transit of the fiftieth oscillation. The amplitude of swing
was noted at the beginning and end, in scale divisions, but is not published for lack of space.
The time was noted by mean time chronometer Negus No. 1809, which was carried to the
observatory for the purpose. It was always placed at the foot and touching the north side of
pier M (figure 2). This chronometer was compared daily with the sidereal chronometer Negus
No. 1769, which was used in the astronomic observations. Determinations of the torsional effect
of the four suspension fibers were made before the first and after the last oscillation sets. The
temperature was noted at the beginning, middle, and end by a Centigrade thermometer, the
bulb of which projected into the magnet-house of the magnetometer. This same thermometer
was used in the deflection observations, readings being taken before and after each set.
Magnet No. 2 was suspended during deflection observations. A solid brass bar with a
carrier supported magnet No. 4 at thirty and forty centimeters from the center. Eight
settings were made and the time and temperature noted as usual. Magnet No. 2 was kept in
magnet box No. 2 outside of the hut (shown on plat) and was brought into the observatory
immediately after preceding oscillation observations. From fifteen to thirty minutes elapsed
before it was observed upon. After deflection, and before the subsequent oscillation observa-
tions, it was returned to magnet box No. 2.
The observation specimens, pages 314 and 315, which together yield an absolute value of
the horizontal intensity, //, will serve to make clear the method of observation and computation.
In the tabulation of results given below, each value of //is deduced from two or more such sets
of oscillation and one set of deflection observations made in the order stated above.
By the aid of the specimens the accompanying tabulation of the condensed original
notes may be readily interpreted. The times given are local mean reckoned from midnight
through twenty-four hours. The mean deflection angles observed at thirty and forty centi-
meters are given in the two columns under heading u. The columns t and t' show the mean
temperature readings for the deflection and oscillation observations respectively. The mean
time of one oscillation corrected for the rate of chronometer appears under column headed T' '.
The effect of ninety degrees of torsion in the suspension is given in the column v. The column
headed /Ogives the finally reduced values for horizontal intensity expressed in gammas, one
gamma being o.ooooi C. G. S. unit. The resulting values of the magnetic moment of magnet
No. 4 at t degrees and at twenty degrees Centigrade are shown in the last two columns respect-
ively. Reference to pages 8 and 10 will serve to explain the remaining headings.
21 *See reference, page 305.
3'4
SCIENTIFIC RESULTS OF ZIEGLER POLAR EXPEDITION
Station: Teplitz Bay Dale: March 19, 1904 Observer: R. R. T.
Instrument : Magnetometer IIII Magnet : No. 4, inverted
Chronometer Negus 1809, daily rate gaining 2. '37 on mean time
Oscillation
number
Chronometer
time
Temp.
V
Extreme scale
reading
Time of
50 oscillations
h m s
7 35 49- 8
14.7
d
593
d
23.0
3
36 20.2
6
50.8
9
37 21.2
12
51-2
15
50
38 22.1
44 15-0
- 14.7
57-1
56.3
26.6
31.0
m 5
8 25.2
53
48.2
28.0
56
45 15-4
24.6
59
48.9
27.7
62
46 16.2
25.0
65
50.3
-14.7
55-3
33-2
28.2
Means
7 4i-3
14.70
57-o
28.4
8 26.45
Formulae :
T = T"(l + *) (i-(/'-/)?) (i + ,) ;W ,(H + X)t=**
Coefficient of torsion. One div. = 1/57
Time of i oscil.
Corr'n for rate*
T'
log T"
" K)
" [i_(</_/) ? ]
(i+M*\
\ m)
II f 3
" ir'K
" w(H + X)
i
10.1290
0.0003
Tors,
circle
Scale
Mean.
Diff's
L. M. L.
oscillations
h m
= u 29
((' -l) =
o.75
o
19
109
289
19
d
40.8
30.4
5-9
40.6
rf
39-8
29.6
48.7
39-2
d
40.30
30.00
49.80
39-9
d
10.30
19.80
9.90
10.1287
2.0IIII
O,OOI26
O.OOOO6
0.00037
d
Mean v = 10.00 = 15. 7
2.0I28O
Remarks :
Chr. to L.
Revolver n
M. T. -
+ 3" 48. -o
to magnet box
3-45257
mioved
1-43977
* Plus for losing rate and minus for gaining rate,
t See page 10.
MAGNETIC OBSERVATIONS
DEFLECTIONS WITH MAGNETOMETER No. mi
Station : Tepiitz Bay Date : March 19, 1904 Observer : R. R. T.
Magnet No. 4 deflecting at right angles to magnet No. 2 suspended
-*J
1
1
i
-a
a
G
X
CIRCLE READINGS
I. Distance r = 30 cm.
II. Distance r = 40 cm.
No.
A
B
Mean
No.
A
B
Mean
i
w
E
W
i
4
/
94 02.5
37 01.5
/
02.2
01.5
/
02.35
01.50
2
3
/
77 25.0
54 05.2
/
24-5
04-5
/
24-75
04.85
2 W
57 00/85
23 19/90
8
W
E
5
8
37 26.5
95 31-2
26.2
30.8
26.35
31.00
6
7
54 05.5
77 47-5
05.0
47.0
05.25
47-25
2 U
58 04/65
23 42/00
r
TT
Formulae : =
m
L'
JO
H
-+ log m (H
255
j
I II
Set
I
II
O / /
3 u (mean) 57 32.75 23 30.95
u 28 46.4 ii 45-5
logC
" Sin
5.86924
9.68246
5-49476
9.30917
A m
lo *S
6.18678
6-18559
logw*(H + X)
1.43960*
8.81319
1.43960*
8.81260
Ended at . 9 51 " *3-9
' l/H(H+X)
H
6759y
6750 r
Mean 9 18.0 ^= 13-95
Chr. to L. M. T. 4- 3 48.0
L. M. T 13 06. o
log wz,
Reduction to 20
logm M
2.64345
0.00441
2.63904
Remarks : Revolver removed to magnet box
m m
435-55
*Mean from four sets oscillations before and after deflections : 1.43977, 1.43959, 1.43974,
and 1.43930.
t See page 10.
316 SCIENTIFIC RESULTS OF ZIEGLER POLAR EXPEDITION
Tabular summary of observations of magnetic horizontal intensity at Teplilz Bay
Date
Local mean
time
H
Centigrade temperature
H
lo * ~m
r = 3ocm. r = 4ocm.
t
/'
;- = 30 cm.
r = 40 cm.
1903
October 12
h nt
17 31
14 59
15 7
ii 04
16 34
16 19
12 06
20 33
9 33
ii 37
16 28
17 48
7 3
ii 06
ii 58
14 47
ii 23
12 12
17 20
7 02
16 40
7 4
20 05
7 43
19 46
20 52
6 33
15 57
13 06
12 16
7 20
16 52
6 55
17 27
7 10
16 54
6 40
17 7
6 5i
16 32
7 oo
l6 21
6 38
16 42
7 35
17 08
/
28 65.0
13.6
29.4
26.9
28 49.0
48.4
46.7
47-8
28 46.0
50.25
34-4
63.55
48.6
45-9
28 44.9
45-7
47-7
47-3
43-o
43-3
42.0
45-9
28 48.9
54-3
53-3
45-2
28 42.7
41-3
46.4
57-0
45-8
28 29.8
50-7
31-4
52.7
44-7
34-9
27.7
45-8
28 25.9
64.9
33-66
40.2
38.2
71.4
24.7
46.2
29.1
58.5
28 45.6
53-4
30.9
44.8
12.4
13-1
28.5
28 12.85*
/
II 56.4
40.6
36.8
35-i
ii 47-3
43-5
41.6
43-2
ii 39.8
44-4
37-7
46.22
45.25
43-8
ii 44.8
42.4
46.8
42.5
42.5
41.0
40.2
45-1
ii 44-3
46.4
48.5
44-75
ii 47.9
47-o
45-5
42.0
42.7
ii 35.75
47-7
39-8
45-4
39-4
35-4
35-3
42.8
ii 34.6
43-i
39-3
38.0
39-7
51-3
35-3
41.6
36.6
47.1
ii 42.6
50.6
38.4
41.1
30.8
54-2
36-9
ii 27.3*
i. 80
+ 8.00
1-55
4-5
- 18.30
15.60
12. OO
- 4.60
-7.80
7.50
4-10
12. OO
18.50
14.25
12.15
12.70
22.40
15.25
2.4O
- 5-00
- 5-65
9.60
13-95
17-25
9-45
2.15
- 4-55
22.80
13-95
17.30
5-25
-3.85
7.00
15-50
23-55
16.25
20 So
o
0.62
+ 5.78
- 2.48
6.09
19.95
16.88
14.28
- 6.12
10-35
- 9-48
- 4.83
I3.5I
19-93
15.26
14.02
12.92
-24.48
16.82
2.23
- 6.36
6.66
12.15
15-73
21. II
- 8.78
2.46
- 5.78
-23.24
I3.6I
18.01
- 6.10
2.70
7-97
- 15-59
22.75
14.50
-19.78
12.48
17-30
11.63
- 12.60
- 4-04
6.02
- 7-32
- 7.00
- 4.40
- 4.76
+ 0.83
- 3.60
+ 6.70
t- 9-45
+ 3-52
-f 1.20
+ 10.72
+ H.I4
+ 10.86
+ 6.63*
6.18222
9387
9041
9106
6.18630
8636
8666
8622
6.18672
8574
8931
8282
8639
8691
6. 18708
8691
8669
8660
8728
8727
8759
8679
6.18621
8505
8509
8676
6. 18740
8818
8678
8443
8670
6.19038
8562
9029
8558
8724
8960
9108
8700
6.19149
8256
8948
8802
8853
8093
9'59
8658
9046
8378
6.18649
8466
8996
8680
9410
8014
9033
6.19413*
6.17872
8802
959
9171
6. 18461
8685
8791
8675
6.18891
8610
9010
8511
8585
8663
6.18596
8745
8501
8745
8713
8810
8861
8572
6.18632
8513
8367
8574
6.18390
8490
8559
8780
8707
6.19130
8408
8910
8589
8937
9'93
9180
8731
6.19222
8706
8912
8998
8898
8>93
9161
8772
9070
8439
6.18687
8198
8952
8791
9400
7978
9025
6. 19629*
22.
29
^O. .
November 9
16
20
V>. .
3. ...
4
7
25-
26
1904
14
IS. .
18. ...
19
25. .
26
2
22 . ...
29....
March I
18....
19....
24
29....
April 4....
5....
n.
12
18
TO
25 ...
26....
12.90
17.40
12.40
- 14.30
4-iS
- 6.30
- 8.25
- 8.00
- 5-25
- 4.25
0.90
- 4-95
+ 5-05
+ 6.65
+ 2.15
+ 0.25
+ 9-90
+ 8.25
+ 9-8o
+ 4-35*
3
9
10.
16
17
1\
24. ...
^o
7 oo
16 49
7 15
20 22
7 58
17 19
7 58
17 22
7 28
20 48
o 42*
^1 . .
June 6. . .
7. ...
13-
14. .
20. ...
21
27
June 28* ..
Observations at the Italian station of 1899 and 1900 ; the results
MAGNETIC OBSERVATIONS
Tabular suminciry of observations of magnetic horizontal intensity at Teplitz Bay
3'7
Effect 90
1 r.
T'
torsion
V
log
m(H-\-X)
log
H
log >,
log m M
Observer
\/H(H+X)
s
/
y
10.2304
25.72
1.43061
8.80554
6646
2.64209
2.63926
W. J. P.
1291
25-40
395
1500
6786
4067
39"
Do.
1276
22.84
3941
1496
6786
4111
3831
Do.
1148
23-77
4033
1586
6799
4106
3788
Do.
10. 1070
28.44
1.44049
8.81297
6756
2-64423
2.63925
Do.
1164
25-03
4001
1331
6761
4341
3878
Do.
1424
26.29
3762
1245
6748
4190
3774
Do.
1382
22.42
3844
1246
6748
4270
3950
Do.
10.1467
22.62 1.43756
8.81269
6752
2.64161
2.63800
Do.
1562
23-33 3677 1134
6731
4216
3857
Do.
1420
24.13 3804
1387
6769
4082
3768
Do.
1637
27-54
3582
0989
6710
4276
3852
Do.
III2
25-94
4O34
1323
6760
4383
3883
Do.
1651
25.34
3586
1132
6731
4131
3686
Do.
10.1242
17.46
1.43992
8.81322
6760
2-64343
2.63925
Do.
1544
i6-73
3755
1237
6747
4193
3768
Do.
1116
19-63
4071
1328
6760
4410
3859
Do
1176
16.42
4056
1379
6768
4344
3886
Do.
1436
12.35
3897
1309
6758
4262
3971
Do.
1333
12.62
3967
1368
6767
4272
3947
Do.
1414
11.26
3912
1361
6765
4217
3884
Do.
1417
12.26
3881
1254
6749
4298
3913
Do.
10.1391
13-29
1.43896
8.81261
6750
2.64304
2.63863
Do.
1258
16.19
3966
1237
6747
4402
39i8
Do.
1830
13-39
3548
993
6710
4234
3851
Do.
1834
13-48
3544
1085
6724
4138
3850
R. R. T.
10. 1423
13-93
1.43881
8.81223
6745
2.64333
2.64014
Do.
0776
22.88
4351
1502
6787
4514
3958
Do.
1322
15-40
396o
1289
6755
4345
3904
Do.
1245
16.96
4000
1306
6757
43 6 3
3878
Do.
1224
16.31
4034
1361
6765
4339
4011
W. J. P.
10.0851
14.78
1.44388
8.81736
6822
2.64307
2.63997
Do.
1590
21-34
3678
1082
6724
4278
3927
Do.
0809
I5-76
4391
1680
6813
4364
3902
Do.
0956
17-63
4251 1412
6773
4504
3938
Do.
1002
15-64
4243 1537
6792
4370
3899
Do.
0404
18.78
4719 1896
6846
4468
3942
Do.
0672
15.30
452i 1832
6836
4336
3908
Do.
0974
18.94
4224 1470
6782 4420
3934
Do.
IO.O53O
16.66
1.44635 8.81910
6848 2.64370
2.63949
Do.
1374 J8-34
3904 1192
6740
4385
3949
Do.
0831
16.69
4379 1655
6810
4385
4071
Do.
1126
17-49
4118 1509
6788
4274
3932
Do.
0946
17.22
4279 , 1577
6798 4362
3995
Do.
1518
17.36
3789 0966
6707 4510
4146
Do.
0506
19.27
4645 1902
6847
4390
4062
Do.
1469
18.13
3814 1264
6751
4222
3907
Do.
0855
20-33
4348 1703
6817
43 01
4029 ' Do.
1413
20.97
3857 1133
6731
4400
4076 ; Do.
10.1318
17.70
I-43976
8.81322
6760
2.64327
2.64133
Do.
2220
18.04
3216 0774
6678
4133
3959
Do.
0900
17.90
4328 , 1651
6809
4334
4102
Do.
1156
18.76
4095 1416
6774
4349
4092
Do.
0499
17.14
4683 2044
6869
4284
4 '53
Do.
1871
17.41
3521 0758
6676
4456
4303
Do.
1358
16.94
3945 1487
6784
4120
3987
Do.
10.1540*
'7-57*
'43793*
8.81657*
6810*
2.63794*
2.63591*
Do.
are for two complete sets each of deflections and oscillations.
SCIENTIFIC RESULTS OF ZIEGLER POLAR EXPEDITION
The following monthly mean values for the logarithm of the magnetic moment of magnet
No. 4 at 20 Centigrade (m m ) and for magnetic horizontal intensity (//) result from these
observations :
Epoch
Number
determi-
nations
Resulting mean values
log m K
H
1903.81
4
2.63864
7
6754
1903.88
4
3882
53
I903-95
6
3808
42
1904.04
8
3894
59
1904.12
4
3870
33
1904.21
5
3953
62
1904.29
8
3931
98
1904.37
10
4012
84
1904.46
7
4104
64
The above mean values of H, each being made up of determinations made at different
times on the days of observation, may be taken practically as applying to mean of day. As
will be noted, the difference between the extreme values is but sixty-five gammas, which, con-
sidering the frequent and rapid fluctuations of this element in high latitudes, is quite satisfac-
tory. From the fifty-six determinations as grouped together in the above tabulation the
resulting horizontal intensity at Teplitz Bay is
6768 r for epoch J904.J6.
SECULAR CHANGE IN MAGNETIC HORIZONTAL INTENSITY
Observations were made for horizontal intensity, as noted in the tabulation of results, at
the magnetic station of the Italian Expedition of 1899 and 1900. Unfortunately opportunity
was afforded only upon this one occasion for observation there. The value obtained seems
somewhat unsatisfactory in view of the unusually low value of the magnetic moment of magnet
No. 4 resulting. A close inspection of the observational data does not, however, disclose any
irregularities of greater amount than the similar work at the hut indicates should be expected
in this region. It is furthermore confirmed in that the result given is derived from two sets of
deflection as well as oscillation observations.
For the purpose of reduction to mean of day a mean curve for diurnal variation in
magnetic horizontal intensity was deduced from the International Observations of 1882 to 1883
at the stations Ssgastyr, Siberia ; Cape Thordsen, Spitzbergen ; Jan Mayen Island ; Karmakul
Bay, Novaia Zemlia, and Bossekop, Norway. Applying diurnal variation corrections so
obtained, the determination at the Italian station on June 28, 1904, becomes 6810 f + 50 f
6860 f. The nearest corresponding observation at the Ziegler Expedition station in point of
time (being but four hours before) is that of the preceding date ; reduced for diurnal variation,
the resulting value is 6784 r + 8 r 6792 r- From these two determinations it appears that
the horizontal intensity at the Ziegler Expedition station is about 68 f smaller than at the
Italian stat ion.
MAGNETIC OBSERVATIONS
Inasmuch as Commander Cagni's observations were, with but one exception, made during
afternoon hours, his values have also been reduced approximately to mean of day by the same
diurnal variation curve (the corrections given are mean values over periods of observation).
These results are as follows, the observed quantities being taken from Professor Palazzo's
discussion :*
Date
No. of
determi-
nations
Local
mean time
Mean
observed
value
Correction
diurnal
variation
Reduced
mean value
Resulting
mean
H
1899
August 29
2
h m h m
14 ^I 17 *\O
r
6842
7
41
7
6801
Y
August 30
4
14 46 - 18 02
6848
41
6807
6805
1900
Tulv 12.
i
17 O7 17 \\
68os
42
68si
1
July 13
4
15 41 - 18 35
6892
41
6851
Tulv 14..
8
Q 08 - 12 w
68 is
6
6820
July 14
i
15 37 - 16 01
6876
43
681-5
6823
July 24...
8
15 10 - 18 35
681 1
3Q
67Q2
July 2$ .
8
IS 2^ - l8 O
6881
7Q
6842
August 3
8
14 40 - 18 09
6849
4O
6809
J
The resulting mean values of 68057 and 6823?- correspond to mean of day for the epochs
1899.66 and 1900.55 respectively. From these the magnetic horizontal intensity at the Italian
station forthe epoch 1900.10136814^. Referred to the Ziegler Expedition station, this becomes
68147 687 = 67467. At the latter location the value derived was 6768 7 for the epoch 1904.16.
Hence the horizontal intensity of the earth's magnetic field has, in the region of Teplitz Bay,
in a period of four years increased 22 7 (0.00022 C. G. S.). Hence, assuming a linear change
during the elapsed interval, the rate of change in magnetic horizontal intensity due to secular
variation is
+ 67 (0.00006 C G. S.) per year.
This rate of increase confirms that adopted by Professor Palazzo in his discussion above
referred to, namely, +97. At the stations Mossel Bay (y = 79 53' N ; A= 16 04' E) and
Cape Thordsen (<f = 78 28' N ; A = 15 42' E) for the periods 1873.5 to 1899.7
1899.7 D r - Solanderf has deduced the annual rates 10 7 and 37 respectively.
1883.2 to
*Osservazioni scieatifiche esequite durante la spedizione Polaredi S. A. R. Luigi Amedeodi Savoia, Duca
degli Abruzzi, 1899-1900. Milan, 1903. Pp. 475-500. (Relazione sulle osservazioni magnetiche fatta dal
Professore Luigi Palazzo.)
fSee reference, page 305.
320
SCIENTIFIC RESULTS OF ZIEGLER POLAR EXPEDITION
SUMMARY SHOWING VAUJBS OF THB MAGNETIC ELEMENTS AND THEIR SECULAR VARIA-
TIONS AT TEPLITZ BAY
The following summarizes the mean results obtained by the expedition at the Teplitz Bay
station. In the case of the declination the value applies to the mean of both day and year ;
this may be said to be practically the case likewise for the inclination and intensity.
A Declination
Epoch
Easterly
declination
Annual rate of
secular change
1900-1904
1904.00
/
22 38.5
/
+ 1%
B Inclination
Epoch
Northerly
inclination
Annual rate of
secular change
1900-1904
1904.13
'
83 12.4
i
2
C Intensity
Annual rate of
Epoch
Horizontal
component
H
Vertical
component
Z
Total
intensity
F
secular change
1900-1904
H
Z
P
1904.16
r
6768
r
56806
r
57208
r
+ 6
-2*38